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Finding the Fourth Proportional to 387.57, 580.71 and 278.88

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Solution

The fourth proportional to 387.57, 580.71 and 278.88 is: 417.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.57 : 580.71 = 278.88 : x
  2. Step 2: Convert to fraction form
    387.57/580.71 = 278.88/x
  3. Step 3: Cross multiply
    387.57x = 580.71 × 278.88
  4. Step 4: Simplify right side
    387.57x = 161,948.40
  5. Step 5: Solve for x
    x = 161,948.40/387.57
  6. Step 6: Final answer
    x = 417.86

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.